Here comes double trouble — scientists have created the first monkey clone, a breakthrough that is likely to stir the debate over the ethical implications of genetic duplication.

The researchers did not use the same technique that spawned Dolly the sheep, in which the nucleus of an adult cell was transplanted into an unfertilized egg.

Instead, they split a very young embryo into four pieces — a method that has been used to clone cows, but had never been used to create a primate.

“This is just artificial twinning,” said Gerald Schatten, who led the groundbreaking research at the Oregon Regional Primate Research Center.

The identical embryos were implanted in different mothers. One of them gave birth to a healthy female rhesus macaque named Tetra, but her twin miscarried.

Now, four more monkeys are pregnant with split embryos. If they give birth in May, “it’s likely that we will have genetically identical monkeys born to different mothers,” Schatten said.

The monkey business could lead to new cures for human disease — but other cloning advances, like the birth of Dolly, have generated a firestorm of controversy.

“We’re sure it will make people discuss the possibility of similar procedures with humans, but that’s not something that we believe should ever be done,” research-center spokesman Jim Parker said.

The Oregon team hopes Tetra and clones to follow will help scientists perfect new lifesaving medical therapies — which are now usually tested on mice.

The monkey clones could be used in the study of embryonic stem cells — from which all organs and tissues grow.

“The possibility of stem-cell therapy could completely change the lives of children,” Schatten said. “No more diabetes, no more Alzheimer’s, no more heart disease. You could repair all these degenerative diseases.”